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What are the minimum and maximum 'FPM' for ceiling diffusers ?
2

What are the minimum and maximum 'FPM' for ceiling diffusers ?

What are the minimum and maximum 'FPM' for ceiling diffusers ?

(OP)
What would be the maximum FPM for a 4way ceiling diffuser in a master bedroom that has 165 SF and no windows ?
Using the 1/1 fpm to cfm ratio, I would need 165 CFM. Should I use two small diffusers or one large one and if so what sizes ?  

RE: What are the minimum and maximum 'FPM' for ceiling diffusers ?

In general, 1 CFM of air is required to heat or cool 1 or 1-1/4 sq. ft. of floor area. I would use 2 diffusers and a take off of a minimum 7”. The Air should travel from the furnace/air conditioner throughout the system at an average velocity of about 700 ft./min
For in depth information go here: http://www.alpinehomeair.com/related/Ductwork.pdf

RE: What are the minimum and maximum 'FPM' for ceiling diffusers ?

50-75 fpm average through room cross-section is a good velocity.

Manufacturer diffuser tables  give throw and velocity (Carnes, Anemostat and etc).

RE: What are the minimum and maximum 'FPM' for ceiling diffusers ?

Well you need to look at the space sensible heat gain to really work out how much air you need.

The FPM will depend on throw and noise.

Maybe go through here and learn how to fish http://www.price-hvac.com/media/trainingModule.aspx#flash

RE: What are the minimum and maximum 'FPM' for ceiling diffusers ?

Good info in the EH Price Catalog, be some selection/layout help in the Metalaire Catlogs, most likely good info from Titus as well.

RE: What are the minimum and maximum 'FPM' for ceiling diffusers ?

(OP)
Thanks for all the responses.
I entered another post yesterday, I have'nt seen it yet, but it should get be there soon.

6x6

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